There is no supported way to prevent VAppCollector from launching other than by disabling Asset Intelligence, although in most cases this is not a viable solution as it stops all licensing information for the System Center Configuration Manager site.
If you are unable to disable Asset Intelligence, the only other known workarounds are below:
1) Include the computer account as part of the App-V user group assigned in the App-V server. This will allow the system account to launch the applications and thus no errors will be reported in the application event log.
2) Use System Center Configuration Manager 2007 to deploy your virtual packages or to deploy your virtual applications using MSI.
3) Ignore the errors in the event logs as they will not affect the App-V operations.
4) Set the HKLM\software\Microsoft\Softgrid\4.5\Client\Configuration\RequireAuthorizationIfCached registry key to 0. Keep in mind that this affects security because any user can create a shortcut and launch the applications even when they are not authorized. Be sure you fully understand all the implications of this before modifying this registry key. See below definition of this key:
RequireAuthorizationIfCached
Indicates that authorization is always required, whether or not an application is already in cache. Possible values:
0=False: Always try to connect to the server. If a connection to the server cannot be established, the client still allows the user to launch an application that has previously been loaded into cache.
1=True (default): Application always must be authorized at startup. For RTSP streamed applications, the user authorization token is sent to the server for authorization. For file-based applications, file ACLs control whether a user may access the application.
Restart the sftlist service for the change to take effect. See http://technet.microsoft.com/en-us/library/dd464849.aspx for more details.